Twice now in the past two months my system has frozen and upon reboot it doesn't post. I've let it cool down for a while and still no go. But when I reseat the CPU everything works again. Actually, I'm not sure if reseating the CPU is necessary, but I do pull the jumper out and place it back as well (jumper free mode).

Any ideas on what's causing this? Specs are below.

Also, my system seems to always run way faster upon a fresh reboot. The memory never runs low as I have Free Ram Optimizer. I think I've tweaked Windows XP to clear the paging file upon rebooting. Isn't there a way for me to manually optimize my system to replicate the rebooting process?